The statements in this section merely provide background information related to the present disclosure and may not constitute prior art. Spark plugs have long been used as igniting means for internal combustion engines of motor vehicles or the like. The spark plug typically includes a center electrode and a ground electrode between which a sparking gap is provided. By applying a high voltage across the center electrode and the ground electrode, a spark discharge takes place in the sparking gap, thereby generating a flame kernel between the center electrode and the ground electrode. As the flame propagates, an air-fuel mixture within the combustion chamber of the engine ignites.
In recent years and due to an increasing demand for low emissions and high efficiency, improvements have been made to better control this combustion process. For example, by encapsulating the spark plug, it is possible to improve mixing of fuel and air and to control initiation of the spark. In such an arrangement, however, the spark plug may experience an increased temperature environment, which tends to reduce its active life. Attempts to alleviate these problems have included insulating the electrodes from one another, as disclosed in U.S. Pat. No. 6,460,506, which issued to Nevinger on Oct. 8, 2002. However, even when employing such a spark plug design, there is still opportunity to reduce heat transfer between the chamber cap and the surrounding environment.